CALIFORNIA LEAST TERN Sterna albifrons browni (Mearns) 



Order: CHARADRIFORMES Family: LARIDAE 



Distinguishing characteristics : A small tern with a yellow bill . Adults are white with 

 a pale gray mantle, forehead white, black cap, wings with a dark area on leading edge. 

 Has quicker wingbeats than other terns, and it can hover for a longer time. 



Present distribution : Breeds along Pacific coast from South San Francisco Bay, 

 California, to southern Baja California. Nonbreeding birds range north to Alameda 

 County in summer . 



Former distribution : Thought to be approximately the same as the present range . 



Status : Critical because of disturbance to limited nesting habitat. Locally common where 

 suitable nesting areas occur. Disappearing from disturbed areas, and nesting temporar- 

 ily on new-made land from dredged sand at Huntington Beach. 



Estimated numbers : In 1970, 300 pairs nested in 15 sites. 



Breeding rate in the wild : Generally two eggs laid in a shallow depression in the sand. 



Reasons for decline : Nesting habitat is being lost because of increased human activity 

 on beaches which are preferred for nesting sites . 



Protective measures already taken : Huntington Beach State Park Tern Sanctuary 

 established by State. Santa Margarita River Tern Sanctuary established on Camp 

 Pendleton Marine Base. Buena Vista Lagoon Ecological Reserve established by State. 

 Nesting habitat developed by Navy at Seal Beach Naval Weapons Station. Classified as 

 endangered under California Game Code . 



Measures proposed : Take measures necessary to protect nesting areas not already 

 protected from motor scooters, dune buggies, and other human encroachment. Restore 

 sites formerly used by terns . Create new artificial sand islands by dredging in 

 protected areas . 



Number in captivity : Unknown . 



Breeding potential in captivity : Unknown . 



References : 



California Department of Fish and Game. 



Grinnell, J. and A. H. Miller. 1944. The distribution of the birds of California . 



Cooper Ornithological Club, Berkeley, California. 

 Hoffman, R. 1927. Birds of the Pacific States . Houghton Mifflin Company , Boston . 

 Kirven .M.N. (in lit^) . 

 Leach, H. R. and L. O. Fisk. 1972. At the crossroads. A report on California's 



Endangered and Rare Fish and Wildlife. California Department of Fish and Game. 



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